1. Field of the Invention
The present invention relates to a file distribution system and method thereof, including a function of a host computer in connection with one or more terminals, for distributing data files to the terminals under management of versions of program applications and data files for use in operating the terminals.
2. Description of the Prior Art
In conventional version up systems for updating program version numbers of data files or applications using networks, there has been used a file distribution system in which copying operations of data files are performed as many times as corresponding to the number of individual terminals and the copied data files are installed to thereby change the old data files and applications into those of new versions in the terminals. Also, there has been used another type of distribution system in which a host computer connected with terminals or an intermediate computer interposed between the host computer and each terminal connected therewith is installed with version management information relating to each terminal and with new data or applications of new versions, so that, based on the version management information, new data files or applications are distributed to a desired terminal requiring a version-up process.
Meanwhile, in the case where only one computer is used, when there is caused a defect due to a hardware or a serious difficulty or trouble such that a system per se is destroyed, the system corresponding to the hardware type thereof must be reinstalled with data files from the initial stage.
FIG. 9 shows an example of a conventional construction of a file distribution system. In this construction, a host computer 100 is connected to a terminal 300 via an intermediate computer 200 interposed between the host computer 100 and the terminal 300. Otherwise, the host computer 100 may be directly connected to the terminal 300 without using an intermediate computer. The host computer 100 includes a version management portion 101 for managing a program version of a subordinate station and a distribution file storage portion 102 for storing a distribution data file to be distributed to a desired subordinate station.
The intermediate computer 200 includes a version management portion 201 managing a program version of the terminal, distribution file storage portion 202 for storing a distribution data file to be distributed to a desired terminal, a version memory portion 203 for storing a program version of the intermediate computer 200 per se, and a file memory portion 204. The terminal 300 includes a version management portion 301 for managing a program version of the terminal per se and a version memory portion 302 for memorizing the program version of the terminal 300 per se. 3
In the case where the host computer 100 is directly connected to the terminal 300 without using an intermediate computer, the program version of the terminal 300 is informed to the version management portion 101 of the host computer 100 at the timing of a start of the communication between the host computer 100 and the terminal 300. Then, in the host computer 100, the informed version of the terminal is compared with the version of the terminal 300 stored by the version management portion 101. When the informed version is not coincident with the managed one stored in the version management portion 101, a version-up file is distributed from the distribution file storage portion 102 of the host computer 100 to the terminal 300. In the terminal 300 distributed with the version-up file, the distributed version-up file is stored in the version management portion 301 to update the old version of the version memory portion 302 in the terminal 300.
Similarly, in the case where the intermediate computer 200 is interposed between the host computer 100 and the terminal 300, the terminal version is compared with the version of the terminal 300 managed by the terminal version management portion 201 in the intermediate computer 200. When the informed terminal version is not coincident with the managed one, a version-up file is distributed from the intermediate computer 200 to the terminal 300.
In the conventional file distribution system, however, it is essentially necessary that the information of the program versions of all of the terminals should be held not only in each terminal but also in the host computer and/or intermediate computer Accordingly, as the number of the terminals is increased, the information of the version management of the terminals to be stored in the version management portions 101 and/or 201 of the host and intermediate computers is increased in amount in proportion thereto, which is wasteful of resources.
Moreover, since the number of hardware types of the terminals is generally by far smaller than the number of the terminals connected to the network system, therefore the information of the versions of the terminals are mostly overlapped.
Furthermore, the performance of each terminal is remarkably improved in a short time recently, and accordingly the applications to be installed in each terminal are increased in function and the process thereof tends to be more and more complicated. Therefore, there has been a problem that, even if the same data file is treated, when applications are successively updated, some performance of the terminals can not be used for the newly updated function thereof, otherwise, although the data file of the application of the old version can be used for the newly updated version, the data file of the application of the new version can not be used for the old version application.